Lyme disease (LD) was mostly unknown in USA until 10 years ago. Its etiology (Borrelia burgdorferi) (Bb) and mode on infection (tick bites) were determined a few years ago. With defined clinical features and serologic tests, LD has been reported in increasing number worldwide. LD has 3 major clinical stages lasting 2 years or longer, with a number of its symptoms and signs very similar to many other disease. It can be cured with antibiotics. Serology plays vital roles in diagnosis and management of LD. The serologic tests available are designed for clinical laboratories, which are often not easily available in suburban and rural areas where LD occurs. A simple, quick, safe and inexpensive serologic test for LD would allow LD diagnosed in physician office or small clinical laboratories and specifically treated earlier and more efficiently. The objective of this research project is to develop such a test. The test will use a simple plastic device and require three sequential additions of two drops of patient blood sample, enzyme-antibody conjugate and substrate, with a few drops os wash solution in between. The test, designated Flex Well ELISA< will take less that 15 minutes and the results will be read visually, with a positive result appearing as a blur dot. The work in Phase I has developed a working model, reagents and procedure; established Bb culture; and collected clinical samples. The Phase II work is to refine the Flex Well ELISA, including the device, procedure and reagents; to test it with serum samples form normal, Lyme disease, syphilis, rheumatic disease; and to send complete test sets to outside investigators for field evaluation during the first year. Minor refinement, preparation of 510K application to the FDC, production scale-up design and preparation of quality control panel of sera will be in the second year of this Phase II plan. The test will be commercialized in Phase III.